# Copyright 1999-2011 Gentoo Foundation
# Distributed under the terms of the GNU General Public License v2

from __future__ import print_function

import errno
import logging
import operator
import platform
import pwd
import random
import re
import shutil
import signal
import socket
import stat
import subprocess
import sys
import tempfile
import textwrap
import time
from itertools import chain

import portage
portage.proxy.lazyimport.lazyimport(globals(),
	'portage.news:count_unread_news,display_news_notifications',
)

from portage import os
from portage import subprocess_getstatusoutput
from portage import _unicode_decode
from portage.cache.cache_errors import CacheError
from portage.const import GLOBAL_CONFIG_PATH
from portage.const import _ENABLE_DYN_LINK_MAP, _ENABLE_SET_CONFIG
from portage.dbapi.dep_expand import dep_expand
from portage.dbapi._expand_new_virt import expand_new_virt
from portage.dep import Atom, extended_cp_match
from portage.eclass_cache import hashed_path
from portage.exception import InvalidAtom
from portage.output import blue, bold, colorize, create_color_func, darkgreen, \
	red, yellow
good = create_color_func("GOOD")
bad = create_color_func("BAD")
from portage.package.ebuild._ipc.QueryCommand import QueryCommand
from portage.package.ebuild.doebuild import _check_temp_dir
from portage._sets import load_default_config, SETPREFIX
from portage._sets.base import InternalPackageSet
from portage.util import cmp_sort_key, writemsg, \
	writemsg_level, writemsg_stdout
from portage.util.digraph import digraph
from portage._global_updates import _global_updates

from _emerge.clear_caches import clear_caches
from _emerge.countdown import countdown
from _emerge.create_depgraph_params import create_depgraph_params
from _emerge.Dependency import Dependency
from _emerge.depgraph import backtrack_depgraph, depgraph, resume_depgraph
from _emerge.DepPrioritySatisfiedRange import DepPrioritySatisfiedRange
from _emerge.emergelog import emergelog
from _emerge.is_valid_package_atom import is_valid_package_atom
from _emerge.MetadataRegen import MetadataRegen
from _emerge.Package import Package
from _emerge.ProgressHandler import ProgressHandler
from _emerge.RootConfig import RootConfig
from _emerge.Scheduler import Scheduler
from _emerge.search import search
from _emerge.SetArg import SetArg
from _emerge.show_invalid_depstring_notice import show_invalid_depstring_notice
from _emerge.sync.getaddrinfo_validate import getaddrinfo_validate
from _emerge.sync.old_tree_timestamp import old_tree_timestamp_warn
from _emerge.unmerge import unmerge
from _emerge.UnmergeDepPriority import UnmergeDepPriority
from _emerge.UseFlagDisplay import pkg_use_display
from _emerge.userquery import userquery

if sys.hexversion >= 0x3000000:
	long = int

def action_build(settings, trees, mtimedb,
	myopts, myaction, myfiles, spinner):

	if '--usepkgonly' not in myopts:
		old_tree_timestamp_warn(settings['PORTDIR'], settings)

	# It's best for config updates in /etc/portage to be processed
	# before we get here, so warn if they're not (bug #267103).
	chk_updated_cfg_files(settings['EROOT'], ['/etc/portage'])

	# validate the state of the resume data
	# so that we can make assumptions later.
	for k in ("resume", "resume_backup"):
		if k not in mtimedb:
			continue
		resume_data = mtimedb[k]
		if not isinstance(resume_data, dict):
			del mtimedb[k]
			continue
		mergelist = resume_data.get("mergelist")
		if not isinstance(mergelist, list):
			del mtimedb[k]
			continue
		for x in mergelist:
			if not (isinstance(x, list) and len(x) == 4):
				continue
			pkg_type, pkg_root, pkg_key, pkg_action = x
			if pkg_root not in trees:
				# Current $ROOT setting differs,
				# so the list must be stale.
				mergelist = None
				break
		if not mergelist:
			del mtimedb[k]
			continue
		resume_opts = resume_data.get("myopts")
		if not isinstance(resume_opts, (dict, list)):
			del mtimedb[k]
			continue
		favorites = resume_data.get("favorites")
		if not isinstance(favorites, list):
			del mtimedb[k]
			continue

	resume = False
	if "--resume" in myopts and \
		("resume" in mtimedb or
		"resume_backup" in mtimedb):
		resume = True
		if "resume" not in mtimedb:
			mtimedb["resume"] = mtimedb["resume_backup"]
			del mtimedb["resume_backup"]
			mtimedb.commit()
		# "myopts" is a list for backward compatibility.
		resume_opts = mtimedb["resume"].get("myopts", [])
		if isinstance(resume_opts, list):
			resume_opts = dict((k,True) for k in resume_opts)
		for opt in ("--ask", "--color", "--skipfirst", "--tree"):
			resume_opts.pop(opt, None)

		# Current options always override resume_opts.
		resume_opts.update(myopts)
		myopts.clear()
		myopts.update(resume_opts)

		if "--debug" in myopts:
			writemsg_level("myopts %s\n" % (myopts,))

		# Adjust config according to options of the command being resumed.
		for myroot in trees:
			mysettings =  trees[myroot]["vartree"].settings
			mysettings.unlock()
			adjust_config(myopts, mysettings)
			mysettings.lock()
			del myroot, mysettings

	ldpath_mtimes = mtimedb["ldpath"]
	favorites=[]
	buildpkgonly = "--buildpkgonly" in myopts
	pretend = "--pretend" in myopts
	fetchonly = "--fetchonly" in myopts or "--fetch-all-uri" in myopts
	ask = "--ask" in myopts
	enter_invalid = '--ask-enter-invalid' in myopts
	nodeps = "--nodeps" in myopts
	oneshot = "--oneshot" in myopts or "--onlydeps" in myopts
	tree = "--tree" in myopts
	if nodeps and tree:
		tree = False
		del myopts["--tree"]
		portage.writemsg(colorize("WARN", " * ") + \
			"--tree is broken with --nodeps. Disabling...\n")
	debug = "--debug" in myopts
	verbose = "--verbose" in myopts
	quiet = "--quiet" in myopts
	myparams = create_depgraph_params(myopts, myaction)

	if pretend or fetchonly:
		# make the mtimedb readonly
		mtimedb.filename = None
	if '--digest' in myopts or 'digest' in settings.features:
		if '--digest' in myopts:
			msg = "The --digest option"
		else:
			msg = "The FEATURES=digest setting"

		msg += " can prevent corruption from being" + \
			" noticed. The `repoman manifest` command is the preferred" + \
			" way to generate manifests and it is capable of doing an" + \
			" entire repository or category at once."
		prefix = bad(" * ")
		writemsg(prefix + "\n")
		from textwrap import wrap
		for line in wrap(msg, 72):
			writemsg("%s%s\n" % (prefix, line))
		writemsg(prefix + "\n")

	if resume:
		favorites = mtimedb["resume"].get("favorites")
		if not isinstance(favorites, list):
			favorites = []

		resume_data = mtimedb["resume"]
		mergelist = resume_data["mergelist"]
		if mergelist and "--skipfirst" in myopts:
			for i, task in enumerate(mergelist):
				if isinstance(task, list) and \
					task and task[-1] == "merge":
					del mergelist[i]
					break

		success = False
		mydepgraph = None
		try:
			success, mydepgraph, dropped_tasks = resume_depgraph(
				settings, trees, mtimedb, myopts, myparams, spinner)
		except (portage.exception.PackageNotFound,
			depgraph.UnsatisfiedResumeDep) as e:
			if isinstance(e, depgraph.UnsatisfiedResumeDep):
				mydepgraph = e.depgraph

			from textwrap import wrap
			from portage.output import EOutput
			out = EOutput()

			resume_data = mtimedb["resume"]
			mergelist = resume_data.get("mergelist")
			if not isinstance(mergelist, list):
				mergelist = []
			if mergelist and debug or (verbose and not quiet):
				out.eerror("Invalid resume list:")
				out.eerror("")
				indent = "  "
				for task in mergelist:
					if isinstance(task, list):
						out.eerror(indent + str(tuple(task)))
				out.eerror("")

			if isinstance(e, depgraph.UnsatisfiedResumeDep):
				out.eerror("One or more packages are either masked or " + \
					"have missing dependencies:")
				out.eerror("")
				indent = "  "
				for dep in e.value:
					if dep.atom is None:
						out.eerror(indent + "Masked package:")
						out.eerror(2 * indent + str(dep.parent))
						out.eerror("")
					else:
						out.eerror(indent + str(dep.atom) + " pulled in by:")
						out.eerror(2 * indent + str(dep.parent))
						out.eerror("")
				msg = "The resume list contains packages " + \
					"that are either masked or have " + \
					"unsatisfied dependencies. " + \
					"Please restart/continue " + \
					"the operation manually, or use --skipfirst " + \
					"to skip the first package in the list and " + \
					"any other packages that may be " + \
					"masked or have missing dependencies."
				for line in wrap(msg, 72):
					out.eerror(line)
			elif isinstance(e, portage.exception.PackageNotFound):
				out.eerror("An expected package is " + \
					"not available: %s" % str(e))
				out.eerror("")
				msg = "The resume list contains one or more " + \
					"packages that are no longer " + \
					"available. Please restart/continue " + \
					"the operation manually."
				for line in wrap(msg, 72):
					out.eerror(line)

		if success:
			if dropped_tasks:
				portage.writemsg("!!! One or more packages have been " + \
					"dropped due to\n" + \
					"!!! masking or unsatisfied dependencies:\n\n",
					noiselevel=-1)
				for task in dropped_tasks:
					portage.writemsg("  " + str(task) + "\n", noiselevel=-1)
				portage.writemsg("\n", noiselevel=-1)
			del dropped_tasks
		else:
			if mydepgraph is not None:
				mydepgraph.display_problems()
			if not (ask or pretend):
				# delete the current list and also the backup
				# since it's probably stale too.
				for k in ("resume", "resume_backup"):
					mtimedb.pop(k, None)
				mtimedb.commit()

			return 1
	else:
		if ("--resume" in myopts):
			print(darkgreen("emerge: It seems we have nothing to resume..."))
			return os.EX_OK

		try:
			success, mydepgraph, favorites = backtrack_depgraph(
				settings, trees, myopts, myparams, myaction, myfiles, spinner)
		except portage.exception.PackageSetNotFound as e:
			root_config = trees[settings['EROOT']]['root_config']
			display_missing_pkg_set(root_config, e.value)
			return 1

		if not success:
			mydepgraph.display_problems()
			return 1

	if "--pretend" not in myopts and \
		("--ask" in myopts or "--tree" in myopts or \
		"--verbose" in myopts) and \
		not ("--quiet" in myopts and "--ask" not in myopts):
		if "--resume" in myopts:
			mymergelist = mydepgraph.altlist()
			if len(mymergelist) == 0:
				print(colorize("INFORM", "emerge: It seems we have nothing to resume..."))
				return os.EX_OK
			favorites = mtimedb["resume"]["favorites"]
			retval = mydepgraph.display(
				mydepgraph.altlist(reversed=tree),
				favorites=favorites)
			mydepgraph.display_problems()
			if retval != os.EX_OK:
				return retval
			prompt="Would you like to resume merging these packages?"
		else:
			retval = mydepgraph.display(
				mydepgraph.altlist(reversed=("--tree" in myopts)),
				favorites=favorites)
			mydepgraph.display_problems()
			if retval != os.EX_OK:
				return retval
			mergecount=0
			for x in mydepgraph.altlist():
				if isinstance(x, Package) and x.operation == "merge":
					mergecount += 1

			if mergecount==0:
				sets = trees[settings['EROOT']]['root_config'].sets
				world_candidates = None
				if "selective" in myparams and \
					not oneshot and favorites:
					# Sets that are not world candidates are filtered
					# out here since the favorites list needs to be
					# complete for depgraph.loadResumeCommand() to
					# operate correctly.
					world_candidates = [x for x in favorites \
						if not (x.startswith(SETPREFIX) and \
						not sets[x[1:]].world_candidate)]
				if "selective" in myparams and \
					not oneshot and world_candidates:
					print()
					for x in world_candidates:
						print(" %s %s" % (good("*"), x))
					prompt="Would you like to add these packages to your world favorites?"
				elif settings["AUTOCLEAN"] and "yes"==settings["AUTOCLEAN"]:
					prompt="Nothing to merge; would you like to auto-clean packages?"
				else:
					print()
					print("Nothing to merge; quitting.")
					print()
					return os.EX_OK
			elif "--fetchonly" in myopts or "--fetch-all-uri" in myopts:
				prompt="Would you like to fetch the source files for these packages?"
			else:
				prompt="Would you like to merge these packages?"
		print()
		if "--ask" in myopts and userquery(prompt, enter_invalid) == "No":
			print()
			print("Quitting.")
			print()
			return os.EX_OK
		# Don't ask again (e.g. when auto-cleaning packages after merge)
		myopts.pop("--ask", None)

	if ("--pretend" in myopts) and not ("--fetchonly" in myopts or "--fetch-all-uri" in myopts):
		if ("--resume" in myopts):
			mymergelist = mydepgraph.altlist()
			if len(mymergelist) == 0:
				print(colorize("INFORM", "emerge: It seems we have nothing to resume..."))
				return os.EX_OK
			favorites = mtimedb["resume"]["favorites"]
			retval = mydepgraph.display(
				mydepgraph.altlist(reversed=tree),
				favorites=favorites)
			mydepgraph.display_problems()
			if retval != os.EX_OK:
				return retval
		else:
			retval = mydepgraph.display(
				mydepgraph.altlist(reversed=("--tree" in myopts)),
				favorites=favorites)
			mydepgraph.display_problems()
			if retval != os.EX_OK:
				return retval
			if "--buildpkgonly" in myopts:
				graph_copy = mydepgraph._dynamic_config.digraph.copy()
				removed_nodes = set()
				for node in graph_copy:
					if not isinstance(node, Package) or \
						node.operation == "nomerge":
						removed_nodes.add(node)
				graph_copy.difference_update(removed_nodes)
				if not graph_copy.hasallzeros(ignore_priority = \
					DepPrioritySatisfiedRange.ignore_medium):
					print("\n!!! --buildpkgonly requires all dependencies to be merged.")
					print("!!! You have to merge the dependencies before you can build this package.\n")
					return 1
	else:
		if "--buildpkgonly" in myopts:
			graph_copy = mydepgraph._dynamic_config.digraph.copy()
			removed_nodes = set()
			for node in graph_copy:
				if not isinstance(node, Package) or \
					node.operation == "nomerge":
					removed_nodes.add(node)
			graph_copy.difference_update(removed_nodes)
			if not graph_copy.hasallzeros(ignore_priority = \
				DepPrioritySatisfiedRange.ignore_medium):
				print("\n!!! --buildpkgonly requires all dependencies to be merged.")
				print("!!! Cannot merge requested packages. Merge deps and try again.\n")
				return 1

		if ("--resume" in myopts):
			favorites=mtimedb["resume"]["favorites"]

		else:
			if "resume" in mtimedb and \
			"mergelist" in mtimedb["resume"] and \
			len(mtimedb["resume"]["mergelist"]) > 1:
				mtimedb["resume_backup"] = mtimedb["resume"]
				del mtimedb["resume"]
				mtimedb.commit()

			mydepgraph.saveNomergeFavorites()

		mergetask = Scheduler(settings, trees, mtimedb, myopts,
			spinner, favorites=favorites,
			graph_config=mydepgraph.schedulerGraph())

		del mydepgraph
		clear_caches(trees)

		retval = mergetask.merge()

		if retval == os.EX_OK and not (buildpkgonly or fetchonly or pretend):
			if "yes" == settings.get("AUTOCLEAN"):
				portage.writemsg_stdout(">>> Auto-cleaning packages...\n")
				unmerge(trees[settings['EROOT']]['root_config'],
					myopts, "clean", [],
					ldpath_mtimes, autoclean=1)
			else:
				portage.writemsg_stdout(colorize("WARN", "WARNING:")
					+ " AUTOCLEAN is disabled.  This can cause serious"
					+ " problems due to overlapping packages.\n")

		return retval

def action_config(settings, trees, myopts, myfiles):
	enter_invalid = '--ask-enter-invalid' in myopts
	if len(myfiles) != 1:
		print(red("!!! config can only take a single package atom at this time\n"))
		sys.exit(1)
	if not is_valid_package_atom(myfiles[0], allow_repo=True):
		portage.writemsg("!!! '%s' is not a valid package atom.\n" % myfiles[0],
			noiselevel=-1)
		portage.writemsg("!!! Please check ebuild(5) for full details.\n")
		portage.writemsg("!!! (Did you specify a version but forget to prefix with '='?)\n")
		sys.exit(1)
	print()
	try:
		pkgs = trees[settings['EROOT']]['vartree'].dbapi.match(myfiles[0])
	except portage.exception.AmbiguousPackageName as e:
		# Multiple matches thrown from cpv_expand
		pkgs = e.args[0]
	if len(pkgs) == 0:
		print("No packages found.\n")
		sys.exit(0)
	elif len(pkgs) > 1:
		if "--ask" in myopts:
			options = []
			print("Please select a package to configure:")
			idx = 0
			for pkg in pkgs:
				idx += 1
				options.append(str(idx))
				print(options[-1]+") "+pkg)
			print("X) Cancel")
			options.append("X")
			idx = userquery("Selection?", enter_invalid, responses=options)
			if idx == "X":
				sys.exit(0)
			pkg = pkgs[int(idx)-1]
		else:
			print("The following packages available:")
			for pkg in pkgs:
				print("* "+pkg)
			print("\nPlease use a specific atom or the --ask option.")
			sys.exit(1)
	else:
		pkg = pkgs[0]

	print()
	if "--ask" in myopts:
		if userquery("Ready to configure %s?" % pkg, enter_invalid) == "No":
			sys.exit(0)
	else:
		print("Configuring pkg...")
	print()
	ebuildpath = trees[settings['EROOT']]['vartree'].dbapi.findname(pkg)
	mysettings = portage.config(clone=settings)
	vardb = trees[mysettings['EROOT']]['vartree'].dbapi
	debug = mysettings.get("PORTAGE_DEBUG") == "1"
	retval = portage.doebuild(ebuildpath, "config", settings=mysettings,
		debug=(settings.get("PORTAGE_DEBUG", "") == 1), cleanup=True,
		mydbapi = trees[settings['EROOT']]['vartree'].dbapi, tree="vartree")
	if retval == os.EX_OK:
		portage.doebuild(ebuildpath, "clean", settings=mysettings,
			debug=debug, mydbapi=vardb, tree="vartree")
	print()

def action_depclean(settings, trees, ldpath_mtimes,
	myopts, action, myfiles, spinner, scheduler=None):
	# Kill packages that aren't explicitly merged or are required as a
	# dependency of another package. World file is explicit.

	# Global depclean or prune operations are not very safe when there are
	# missing dependencies since it's unknown how badly incomplete
	# the dependency graph is, and we might accidentally remove packages
	# that should have been pulled into the graph. On the other hand, it's
	# relatively safe to ignore missing deps when only asked to remove
	# specific packages.

	msg = []
	if not _ENABLE_DYN_LINK_MAP:
		msg.append("Depclean may break link level dependencies. Thus, it is\n")
		msg.append("recommended to use a tool such as " + good("`revdep-rebuild`") + " (from\n")
		msg.append("app-portage/gentoolkit) in order to detect such breakage.\n")
		msg.append("\n")
	msg.append("Always study the list of packages to be cleaned for any obvious\n")
	msg.append("mistakes. Packages that are part of the world set will always\n")
	msg.append("be kept.  They can be manually added to this set with\n")
	msg.append(good("`emerge --noreplace <atom>`") + ".  Packages that are listed in\n")
	msg.append("package.provided (see portage(5)) will be removed by\n")
	msg.append("depclean, even if they are part of the world set.\n")
	msg.append("\n")
	msg.append("As a safety measure, depclean will not remove any packages\n")
	msg.append("unless *all* required dependencies have been resolved.  As a\n")
	msg.append("consequence, it is often necessary to run %s\n" % \
		good("`emerge --update"))
	msg.append(good("--newuse --deep @world`") + \
		" prior to depclean.\n")

	if action == "depclean" and "--quiet" not in myopts and not myfiles:
		portage.writemsg_stdout("\n")
		for x in msg:
			portage.writemsg_stdout(colorize("WARN", " * ") + x)

	root_config = trees[settings['EROOT']]['root_config']
	vardb = root_config.trees['vartree'].dbapi

	args_set = InternalPackageSet(allow_repo=True)
	if myfiles:
		args_set.update(myfiles)
		matched_packages = False
		for x in args_set:
			if vardb.match(x):
				matched_packages = True
			else:
				writemsg_level("--- Couldn't find '%s' to %s.\n" % \
					(x.replace("null/", ""), action),
					level=logging.WARN, noiselevel=-1)
		if not matched_packages:
			writemsg_level(">>> No packages selected for removal by %s\n" % \
				action)
			return 0

	# The calculation is done in a separate function so that depgraph
	# references go out of scope and the corresponding memory
	# is freed before we call unmerge().
	rval, cleanlist, ordered, req_pkg_count = \
		calc_depclean(settings, trees, ldpath_mtimes,
			myopts, action, args_set, spinner)

	clear_caches(trees)

	if rval != os.EX_OK:
		return rval

	if cleanlist:
		unmerge(root_config, myopts, "unmerge",
			cleanlist, ldpath_mtimes, ordered=ordered,
			scheduler=scheduler)

	if action == "prune":
		return

	if not cleanlist and "--quiet" in myopts:
		return

	print("Packages installed:   " + str(len(vardb.cpv_all())))
	print("Packages in world:    " + \
		str(len(root_config.sets["selected"].getAtoms())))
	print("Packages in system:   " + \
		str(len(root_config.sets["system"].getAtoms())))
	print("Required packages:    "+str(req_pkg_count))
	if "--pretend" in myopts:
		print("Number to remove:     "+str(len(cleanlist)))
	else:
		print("Number removed:       "+str(len(cleanlist)))

def calc_depclean(settings, trees, ldpath_mtimes,
	myopts, action, args_set, spinner):
	allow_missing_deps = bool(args_set)

	debug = '--debug' in myopts
	xterm_titles = "notitles" not in settings.features
	root_len = len(settings["ROOT"])
	eroot = settings['EROOT']
	root_config = trees[eroot]["root_config"]
	psets = root_config.setconfig.psets
	deselect = myopts.get('--deselect') != 'n'
	required_sets = {}
	required_sets['world'] = psets['world']

	# When removing packages, a temporary version of the world 'selected'
	# set may be used which excludes packages that are intended to be
	# eligible for removal.
	selected_set = psets['selected']
	required_sets['selected'] = selected_set
	protected_set = InternalPackageSet()
	protected_set_name = '____depclean_protected_set____'
	required_sets[protected_set_name] = protected_set
	system_set = psets["system"]

	if not system_set or not selected_set:

		if not system_set:
			writemsg_level("!!! You have no system list.\n",
				level=logging.ERROR, noiselevel=-1)

		if not selected_set:
			writemsg_level("!!! You have no world file.\n",
					level=logging.WARNING, noiselevel=-1)

		writemsg_level("!!! Proceeding is likely to " + \
			"break your installation.\n",
			level=logging.WARNING, noiselevel=-1)
		if "--pretend" not in myopts:
			countdown(int(settings["EMERGE_WARNING_DELAY"]), ">>> Depclean")

	if action == "depclean":
		emergelog(xterm_titles, " >>> depclean")

	writemsg_level("\nCalculating dependencies  ")
	resolver_params = create_depgraph_params(myopts, "remove")
	resolver = depgraph(settings, trees, myopts, resolver_params, spinner)
	resolver._load_vdb()
	vardb = resolver._frozen_config.trees[eroot]["vartree"].dbapi
	real_vardb = trees[eroot]["vartree"].dbapi

	if action == "depclean":

		if args_set:

			if deselect:
				# Start with an empty set.
				selected_set = InternalPackageSet()
				required_sets['selected'] = selected_set
				# Pull in any sets nested within the selected set.
				selected_set.update(psets['selected'].getNonAtoms())

			# Pull in everything that's installed but not matched
			# by an argument atom since we don't want to clean any
			# package if something depends on it.
			for pkg in vardb:
				if spinner:
					spinner.update()

				try:
					if args_set.findAtomForPackage(pkg) is None:
						protected_set.add("=" + pkg.cpv)
						continue
				except portage.exception.InvalidDependString as e:
					show_invalid_depstring_notice(pkg,
						pkg.metadata["PROVIDE"], str(e))
					del e
					protected_set.add("=" + pkg.cpv)
					continue

	elif action == "prune":

		if deselect:
			# Start with an empty set.
			selected_set = InternalPackageSet()
			required_sets['selected'] = selected_set
			# Pull in any sets nested within the selected set.
			selected_set.update(psets['selected'].getNonAtoms())

		# Pull in everything that's installed since we don't
		# to prune a package if something depends on it.
		protected_set.update(vardb.cp_all())

		if not args_set:

			# Try to prune everything that's slotted.
			for cp in vardb.cp_all():
				if len(vardb.cp_list(cp)) > 1:
					args_set.add(cp)

		# Remove atoms from world that match installed packages
		# that are also matched by argument atoms, but do not remove
		# them if they match the highest installed version.
		for pkg in vardb:
			if spinner is not None:
				spinner.update()
			pkgs_for_cp = vardb.match_pkgs(pkg.cp)
			if not pkgs_for_cp or pkg not in pkgs_for_cp:
				raise AssertionError("package expected in matches: " + \
					"cp = %s, cpv = %s matches = %s" % \
					(pkg.cp, pkg.cpv, [str(x) for x in pkgs_for_cp]))

			highest_version = pkgs_for_cp[-1]
			if pkg == highest_version:
				# pkg is the highest version
				protected_set.add("=" + pkg.cpv)
				continue

			if len(pkgs_for_cp) <= 1:
				raise AssertionError("more packages expected: " + \
					"cp = %s, cpv = %s matches = %s" % \
					(pkg.cp, pkg.cpv, [str(x) for x in pkgs_for_cp]))

			try:
				if args_set.findAtomForPackage(pkg) is None:
					protected_set.add("=" + pkg.cpv)
					continue
			except portage.exception.InvalidDependString as e:
				show_invalid_depstring_notice(pkg,
					pkg.metadata["PROVIDE"], str(e))
				del e
				protected_set.add("=" + pkg.cpv)
				continue

	if resolver._frozen_config.excluded_pkgs:
		excluded_set = resolver._frozen_config.excluded_pkgs
		required_sets['__excluded__'] = InternalPackageSet()

		for pkg in vardb:
			if spinner:
				spinner.update()

			try:
				if excluded_set.findAtomForPackage(pkg):
					required_sets['__excluded__'].add("=" + pkg.cpv)
			except portage.exception.InvalidDependString as e:
				show_invalid_depstring_notice(pkg,
					pkg.metadata["PROVIDE"], str(e))
				del e
				required_sets['__excluded__'].add("=" + pkg.cpv)

	success = resolver._complete_graph(required_sets={eroot:required_sets})
	writemsg_level("\b\b... done!\n")

	resolver.display_problems()

	if not success:
		return 1, [], False, 0

	def unresolved_deps():

		unresolvable = set()
		for dep in resolver._dynamic_config._initially_unsatisfied_deps:
			if isinstance(dep.parent, Package) and \
				(dep.priority > UnmergeDepPriority.SOFT):
				unresolvable.add((dep.atom, dep.parent.cpv))

		if not unresolvable:
			return False

		if unresolvable and not allow_missing_deps:

			if "--debug" in myopts:
				writemsg("\ndigraph:\n\n", noiselevel=-1)
				resolver._dynamic_config.digraph.debug_print()
				writemsg("\n", noiselevel=-1)

			prefix = bad(" * ")
			msg = []
			msg.append("Dependencies could not be completely resolved due to")
			msg.append("the following required packages not being installed:")
			msg.append("")
			for atom, parent in unresolvable:
				msg.append("  %s pulled in by:" % (atom,))
				msg.append("    %s" % (parent,))
				msg.append("")
			msg.extend(textwrap.wrap(
				"Have you forgotten to do a complete update prior " + \
				"to depclean? The most comprehensive command for this " + \
				"purpose is as follows:", 65
			))
			msg.append("")
			msg.append("  " + \
				good("emerge --update --newuse --deep --with-bdeps=y @world"))
			msg.append("")
			msg.extend(textwrap.wrap(
				"Note that the --with-bdeps=y option is not required in " + \
				"many situations. Refer to the emerge manual page " + \
				"(run `man emerge`) for more information about " + \
				"--with-bdeps.", 65
			))
			msg.append("")
			msg.extend(textwrap.wrap(
				"Also, note that it may be necessary to manually uninstall " + \
				"packages that no longer exist in the portage tree, since " + \
				"it may not be possible to satisfy their dependencies.", 65
			))
			if action == "prune":
				msg.append("")
				msg.append("If you would like to ignore " + \
					"dependencies then use %s." % good("--nodeps"))
			writemsg_level("".join("%s%s\n" % (prefix, line) for line in msg),
				level=logging.ERROR, noiselevel=-1)
			return True
		return False

	if unresolved_deps():
		return 1, [], False, 0

	graph = resolver._dynamic_config.digraph.copy()
	required_pkgs_total = 0
	for node in graph:
		if isinstance(node, Package):
			required_pkgs_total += 1

	def show_parents(child_node):
		parent_nodes = graph.parent_nodes(child_node)
		if not parent_nodes:
			# With --prune, the highest version can be pulled in without any
			# real parent since all installed packages are pulled in.  In that
			# case there's nothing to show here.
			return
		parent_strs = []
		for node in parent_nodes:
			parent_strs.append(str(getattr(node, "cpv", node)))
		parent_strs.sort()
		msg = []
		msg.append("  %s pulled in by:\n" % (child_node.cpv,))
		for parent_str in parent_strs:
			msg.append("    %s\n" % (parent_str,))
		msg.append("\n")
		portage.writemsg_stdout("".join(msg), noiselevel=-1)

	def cmp_pkg_cpv(pkg1, pkg2):
		"""Sort Package instances by cpv."""
		if pkg1.cpv > pkg2.cpv:
			return 1
		elif pkg1.cpv == pkg2.cpv:
			return 0
		else:
			return -1

	def create_cleanlist():

		if "--debug" in myopts:
			writemsg("\ndigraph:\n\n", noiselevel=-1)
			graph.debug_print()
			writemsg("\n", noiselevel=-1)

		# Never display the special internal protected_set.
		for node in graph:
			if isinstance(node, SetArg) and node.name == protected_set_name:
				graph.remove(node)
				break

		pkgs_to_remove = []

		if action == "depclean":
			if args_set:

				for pkg in sorted(vardb, key=cmp_sort_key(cmp_pkg_cpv)):
					arg_atom = None
					try:
						arg_atom = args_set.findAtomForPackage(pkg)
					except portage.exception.InvalidDependString:
						# this error has already been displayed by now
						continue

					if arg_atom:
						if pkg not in graph:
							pkgs_to_remove.append(pkg)
						elif "--verbose" in myopts:
							show_parents(pkg)

			else:
				for pkg in sorted(vardb, key=cmp_sort_key(cmp_pkg_cpv)):
					if pkg not in graph:
						pkgs_to_remove.append(pkg)
					elif "--verbose" in myopts:
						show_parents(pkg)

		elif action == "prune":

			for atom in args_set:
				for pkg in vardb.match_pkgs(atom):
					if pkg not in graph:
						pkgs_to_remove.append(pkg)
					elif "--verbose" in myopts:
						show_parents(pkg)

		if not pkgs_to_remove:
			writemsg_level(
				">>> No packages selected for removal by %s\n" % action)
			if "--verbose" not in myopts:
				writemsg_level(
					">>> To see reverse dependencies, use %s\n" % \
						good("--verbose"))
			if action == "prune":
				writemsg_level(
					">>> To ignore dependencies, use %s\n" % \
						good("--nodeps"))

		return pkgs_to_remove

	cleanlist = create_cleanlist()
	clean_set = set(cleanlist)

	if cleanlist and \
		real_vardb._linkmap is not None and \
		myopts.get("--depclean-lib-check") != "n" and \
		"preserve-libs" not in settings.features:

		# Check if any of these packages are the sole providers of libraries
		# with consumers that have not been selected for removal. If so, these
		# packages and any dependencies need to be added to the graph.
		linkmap = real_vardb._linkmap
		consumer_cache = {}
		provider_cache = {}
		consumer_map = {}

		writemsg_level(">>> Checking for lib consumers...\n")

		for pkg in cleanlist:
			pkg_dblink = real_vardb._dblink(pkg.cpv)
			consumers = {}

			for lib in pkg_dblink.getcontents():
				lib = lib[root_len:]
				lib_key = linkmap._obj_key(lib)
				lib_consumers = consumer_cache.get(lib_key)
				if lib_consumers is None:
					try:
						lib_consumers = linkmap.findConsumers(lib_key)
					except KeyError:
						continue
					consumer_cache[lib_key] = lib_consumers
				if lib_consumers:
					consumers[lib_key] = lib_consumers

			if not consumers:
				continue

			for lib, lib_consumers in list(consumers.items()):
				for consumer_file in list(lib_consumers):
					if pkg_dblink.isowner(consumer_file):
						lib_consumers.remove(consumer_file)
				if not lib_consumers:
					del consumers[lib]

			if not consumers:
				continue

			for lib, lib_consumers in consumers.items():

				soname = linkmap.getSoname(lib)

				consumer_providers = []
				for lib_consumer in lib_consumers:
					providers = provider_cache.get(lib)
					if providers is None:
						providers = linkmap.findProviders(lib_consumer)
						provider_cache[lib_consumer] = providers
					if soname not in providers:
						# Why does this happen?
						continue
					consumer_providers.append(
						(lib_consumer, providers[soname]))

				consumers[lib] = consumer_providers

			consumer_map[pkg] = consumers

		if consumer_map:

			search_files = set()
			for consumers in consumer_map.values():
				for lib, consumer_providers in consumers.items():
					for lib_consumer, providers in consumer_providers:
						search_files.add(lib_consumer)
						search_files.update(providers)

			writemsg_level(">>> Assigning files to packages...\n")
			file_owners = {}
			for f in search_files:
				owner_set = set()
				for owner in linkmap.getOwners(f):
					owner_dblink = real_vardb._dblink(owner)
					if owner_dblink.exists():
						owner_set.add(owner_dblink)
				if owner_set:
					file_owners[f] = owner_set

			for pkg, consumers in list(consumer_map.items()):
				for lib, consumer_providers in list(consumers.items()):
					lib_consumers = set()

					for lib_consumer, providers in consumer_providers:
						owner_set = file_owners.get(lib_consumer)
						provider_dblinks = set()
						provider_pkgs = set()

						if len(providers) > 1:
							for provider in providers:
								provider_set = file_owners.get(provider)
								if provider_set is not None:
									provider_dblinks.update(provider_set)

						if len(provider_dblinks) > 1:
							for provider_dblink in provider_dblinks:
								provider_pkg = resolver._pkg(
									provider_dblink.mycpv, "installed",
									root_config, installed=True)
								if provider_pkg not in clean_set:
									provider_pkgs.add(provider_pkg)

						if provider_pkgs:
							continue

						if owner_set is not None:
							lib_consumers.update(owner_set)

					for consumer_dblink in list(lib_consumers):
						if resolver._pkg(consumer_dblink.mycpv, "installed",
							root_config, installed=True) in clean_set:
							lib_consumers.remove(consumer_dblink)
							continue

					if lib_consumers:
						consumers[lib] = lib_consumers
					else:
						del consumers[lib]
				if not consumers:
					del consumer_map[pkg]

		if consumer_map:
			# TODO: Implement a package set for rebuilding consumer packages.

			msg = "In order to avoid breakage of link level " + \
				"dependencies, one or more packages will not be removed. " + \
				"This can be solved by rebuilding " + \
				"the packages that pulled them in."

			prefix = bad(" * ")
			from textwrap import wrap
			writemsg_level("".join(prefix + "%s\n" % line for \
				line in wrap(msg, 70)), level=logging.WARNING, noiselevel=-1)

			msg = []
			for pkg in sorted(consumer_map, key=cmp_sort_key(cmp_pkg_cpv)):
				consumers = consumer_map[pkg]
				consumer_libs = {}
				for lib, lib_consumers in consumers.items():
					for consumer in lib_consumers:
						consumer_libs.setdefault(
							consumer.mycpv, set()).add(linkmap.getSoname(lib))
				unique_consumers = set(chain(*consumers.values()))
				unique_consumers = sorted(consumer.mycpv \
					for consumer in unique_consumers)
				msg.append("")
				msg.append("  %s pulled in by:" % (pkg.cpv,))
				for consumer in unique_consumers:
					libs = consumer_libs[consumer]
					msg.append("    %s needs %s" % \
						(consumer, ', '.join(sorted(libs))))
			msg.append("")
			writemsg_level("".join(prefix + "%s\n" % line for line in msg),
				level=logging.WARNING, noiselevel=-1)

			# Add lib providers to the graph as children of lib consumers,
			# and also add any dependencies pulled in by the provider.
			writemsg_level(">>> Adding lib providers to graph...\n")

			for pkg, consumers in consumer_map.items():
				for consumer_dblink in set(chain(*consumers.values())):
					consumer_pkg = resolver._pkg(consumer_dblink.mycpv,
						"installed", root_config, installed=True)
					if not resolver._add_pkg(pkg,
						Dependency(parent=consumer_pkg,
						priority=UnmergeDepPriority(runtime=True),
						root=pkg.root)):
						resolver.display_problems()
						return 1, [], False, 0

			writemsg_level("\nCalculating dependencies  ")
			success = resolver._complete_graph(
				required_sets={eroot:required_sets})
			writemsg_level("\b\b... done!\n")
			resolver.display_problems()
			if not success:
				return 1, [], False, 0
			if unresolved_deps():
				return 1, [], False, 0

			graph = resolver._dynamic_config.digraph.copy()
			required_pkgs_total = 0
			for node in graph:
				if isinstance(node, Package):
					required_pkgs_total += 1
			cleanlist = create_cleanlist()
			if not cleanlist:
				return 0, [], False, required_pkgs_total
			clean_set = set(cleanlist)

	if clean_set:
		writemsg_level(">>> Calculating removal order...\n")
		# Use a topological sort to create an unmerge order such that
		# each package is unmerged before it's dependencies. This is
		# necessary to avoid breaking things that may need to run
		# during pkg_prerm or pkg_postrm phases.

		# Create a new graph to account for dependencies between the
		# packages being unmerged.
		graph = digraph()
		del cleanlist[:]

		dep_keys = ["DEPEND", "RDEPEND", "PDEPEND"]
		runtime = UnmergeDepPriority(runtime=True)
		runtime_post = UnmergeDepPriority(runtime_post=True)
		buildtime = UnmergeDepPriority(buildtime=True)
		priority_map = {
			"RDEPEND": runtime,
			"PDEPEND": runtime_post,
			"DEPEND": buildtime,
		}

		for node in clean_set:
			graph.add(node, None)
			for dep_type in dep_keys:
				depstr = node.metadata[dep_type]
				if not depstr:
					continue
				priority = priority_map[dep_type]

				if debug:
					writemsg_level(_unicode_decode("\nParent:    %s\n") \
						% (node,), noiselevel=-1, level=logging.DEBUG)
					writemsg_level(_unicode_decode(  "Depstring: %s\n") \
						% (depstr,), noiselevel=-1, level=logging.DEBUG)
					writemsg_level(_unicode_decode(  "Priority:  %s\n") \
						% (priority,), noiselevel=-1, level=logging.DEBUG)

				try:
					atoms = resolver._select_atoms(eroot, depstr,
						myuse=node.use.enabled, parent=node,
						priority=priority)[node]
				except portage.exception.InvalidDependString:
					# Ignore invalid deps of packages that will
					# be uninstalled anyway.
					continue

				if debug:
					writemsg_level("Candidates: [%s]\n" % \
						', '.join(_unicode_decode("'%s'") % (x,) for x in atoms),
						noiselevel=-1, level=logging.DEBUG)

				for atom in atoms:
					if not isinstance(atom, portage.dep.Atom):
						# Ignore invalid atoms returned from dep_check().
						continue
					if atom.blocker:
						continue
					matches = vardb.match_pkgs(atom)
					if not matches:
						continue
					for child_node in matches:
						if child_node in clean_set:
							graph.add(child_node, node, priority=priority)

		if debug:
			writemsg_level("\nunmerge digraph:\n\n",
				noiselevel=-1, level=logging.DEBUG)
			graph.debug_print()
			writemsg_level("\n", noiselevel=-1, level=logging.DEBUG)

		ordered = True
		if len(graph.order) == len(graph.root_nodes()):
			# If there are no dependencies between packages
			# let unmerge() group them by cat/pn.
			ordered = False
			cleanlist = [pkg.cpv for pkg in graph.order]
		else:
			# Order nodes from lowest to highest overall reference count for
			# optimal root node selection (this can help minimize issues
			# with unaccounted implicit dependencies).
			node_refcounts = {}
			for node in graph.order:
				node_refcounts[node] = len(graph.parent_nodes(node))
			def cmp_reference_count(node1, node2):
				return node_refcounts[node1] - node_refcounts[node2]
			graph.order.sort(key=cmp_sort_key(cmp_reference_count))

			ignore_priority_range = [None]
			ignore_priority_range.extend(
				range(UnmergeDepPriority.MIN, UnmergeDepPriority.MAX + 1))
			while graph:
				for ignore_priority in ignore_priority_range:
					nodes = graph.root_nodes(ignore_priority=ignore_priority)
					if nodes:
						break
				if not nodes:
					raise AssertionError("no root nodes")
				if ignore_priority is not None:
					# Some deps have been dropped due to circular dependencies,
					# so only pop one node in order to minimize the number that
					# are dropped.
					del nodes[1:]
				for node in nodes:
					graph.remove(node)
					cleanlist.append(node.cpv)

		return 0, cleanlist, ordered, required_pkgs_total
	return 0, [], False, required_pkgs_total

def action_deselect(settings, trees, opts, atoms):
	enter_invalid = '--ask-enter-invalid' in opts
	root_config = trees[settings['EROOT']]['root_config']
	world_set = root_config.sets['selected']
	if not hasattr(world_set, 'update'):
		writemsg_level("World @selected set does not appear to be mutable.\n",
			level=logging.ERROR, noiselevel=-1)
		return 1

	pretend = '--pretend' in opts
	locked = False
	if not pretend and hasattr(world_set, 'lock'):
		world_set.lock()
		locked = True
	try:
		world_set.load()
		world_atoms = world_set.getAtoms()
		vardb = root_config.trees["vartree"].dbapi
		expanded_atoms = set(atoms)

		for atom in atoms:
			if not atom.startswith(SETPREFIX):
				if atom.cp.startswith("null/"):
					# try to expand category from world set
					null_cat, pn = portage.catsplit(atom.cp)
					for world_atom in world_atoms:
						cat, world_pn = portage.catsplit(world_atom.cp)
						if pn == world_pn:
							expanded_atoms.add(
								Atom(atom.replace("null", cat, 1),
								allow_repo=True, allow_wildcard=True))

				for cpv in vardb.match(atom):
					slot, = vardb.aux_get(cpv, ["SLOT"])
					if not slot:
						slot = "0"
					expanded_atoms.add(Atom("%s:%s" % \
						(portage.cpv_getkey(cpv), slot)))

		discard_atoms = set()
		for atom in world_set:
			for arg_atom in expanded_atoms:
				if arg_atom.startswith(SETPREFIX):
					if atom.startswith(SETPREFIX) and \
						arg_atom == atom:
						discard_atoms.add(atom)
						break
				else:
					if not atom.startswith(SETPREFIX) and \
						arg_atom.intersects(atom) and \
						not (arg_atom.slot and not atom.slot) and \
						not (arg_atom.repo and not atom.repo):
						discard_atoms.add(atom)
						break
		if discard_atoms:
			for atom in sorted(discard_atoms):
				if pretend:
					print(">>> Would remove %s from \"world\" favorites file..." % \
						colorize("INFORM", str(atom)))
				else:
					print(">>> Removing %s from \"world\" favorites file..." % \
						colorize("INFORM", str(atom)))

			if '--ask' in opts:
				prompt = "Would you like to remove these " + \
					"packages from your world favorites?"
				if userquery(prompt, enter_invalid) == 'No':
					return os.EX_OK

			remaining = set(world_set)
			remaining.difference_update(discard_atoms)
			if not pretend:
				world_set.replace(remaining)
		else:
			print(">>> No matching atoms found in \"world\" favorites file...")
	finally:
		if locked:
			world_set.unlock()
	return os.EX_OK

class _info_pkgs_ver(object):
	def __init__(self, ver, repo_suffix, provide_suffix):
		self.ver = ver
		self.repo_suffix = repo_suffix
		self.provide_suffix = provide_suffix

	def __lt__(self, other):
		return portage.versions.vercmp(self.ver, other.ver) < 0

	def toString(self):
		"""
		This may return unicode if repo_name contains unicode.
		Don't use __str__ and str() since unicode triggers compatibility
		issues between python 2.x and 3.x.
		"""
		return self.ver + self.repo_suffix + self.provide_suffix

def action_info(settings, trees, myopts, myfiles):

	output_buffer = []
	append = output_buffer.append
	root_config = trees[settings['EROOT']]['root_config']
	running_eroot = trees._running_eroot

	append(getportageversion(settings["PORTDIR"], None,
		settings.profile_path, settings["CHOST"],
		trees[settings['EROOT']]["vartree"].dbapi))

	header_width = 65
	header_title = "System Settings"
	if myfiles:
		append(header_width * "=")
		append(header_title.rjust(int(header_width/2 + len(header_title)/2)))
	append(header_width * "=")
	append("System uname: %s" % (platform.platform(aliased=1),))

	lastSync = portage.grabfile(os.path.join(
		settings["PORTDIR"], "metadata", "timestamp.chk"))
	if lastSync:
		lastSync = lastSync[0]
	else:
		lastSync = "Unknown"
	append("Timestamp of tree: %s" % (lastSync,))

	output=subprocess_getstatusoutput("distcc --version")
	if output[0] == os.EX_OK:
		distcc_str = output[1].split("\n", 1)[0]
		if "distcc" in settings.features:
			distcc_str += " [enabled]"
		else:
			distcc_str += " [disabled]"
		append(distcc_str)

	output=subprocess_getstatusoutput("ccache -V")
	if output[0] == os.EX_OK:
		ccache_str = output[1].split("\n", 1)[0]
		if "ccache" in settings.features:
			ccache_str += " [enabled]"
		else:
			ccache_str += " [disabled]"
		append(ccache_str)

	myvars  = ["sys-devel/autoconf", "sys-devel/automake", "virtual/os-headers",
	           "sys-devel/binutils", "sys-devel/libtool",  "dev-lang/python"]
	myvars += portage.util.grabfile(settings["PORTDIR"]+"/profiles/info_pkgs")
	atoms = []
	vardb = trees[running_eroot]['vartree'].dbapi
	for x in myvars:
		try:
			x = Atom(x)
		except InvalidAtom:
			append("%-20s %s" % (x+":", "[NOT VALID]"))
		else:
			for atom in expand_new_virt(vardb, x):
				if not atom.blocker:
					atoms.append((x, atom))

	myvars = sorted(set(atoms))

	portdb = trees[running_eroot]['porttree'].dbapi
	main_repo = portdb.getRepositoryName(portdb.porttree_root)
	cp_map = {}
	cp_max_len = 0

	for orig_atom, x in myvars:
			pkg_matches = vardb.match(x)

			versions = []
			for cpv in pkg_matches:
				matched_cp = portage.versions.cpv_getkey(cpv)
				ver = portage.versions.cpv_getversion(cpv)
				ver_map = cp_map.setdefault(matched_cp, {})
				prev_match = ver_map.get(ver)
				if prev_match is not None:
					if prev_match.provide_suffix:
						# prefer duplicate matches that include
						# additional virtual provider info
						continue

				if len(matched_cp) > cp_max_len:
					cp_max_len = len(matched_cp)
				repo = vardb.aux_get(cpv, ["repository"])[0]
				if repo == main_repo:
					repo_suffix = ""
				elif not repo:
					repo_suffix = "::<unknown repository>"
				else:
					repo_suffix = "::" + repo

				if matched_cp == orig_atom.cp:
					provide_suffix = ""
				else:
					provide_suffix = " (%s)" % (orig_atom,)

				ver_map[ver] = _info_pkgs_ver(ver, repo_suffix, provide_suffix)

	for cp in sorted(cp_map):
		versions = sorted(cp_map[cp].values())
		versions = ", ".join(ver.toString() for ver in versions)
		append("%s %s" % \
			((cp + ":").ljust(cp_max_len + 1), versions))

	repos = portdb.settings.repositories
	if "--verbose" in myopts:
		append("Repositories:\n")
		for repo in repos:
			append(repo.info_string())
	else:
		append("Repositories: %s" % \
			" ".join(repo.name for repo in repos))

	if _ENABLE_SET_CONFIG:
		sets_line = "Installed sets: "
		sets_line += ", ".join(s for s in \
			sorted(root_config.sets['selected'].getNonAtoms()) \
			if s.startswith(SETPREFIX))
		append(sets_line)

	if "--verbose" in myopts:
		myvars = list(settings)
	else:
		myvars = ['GENTOO_MIRRORS', 'CONFIG_PROTECT', 'CONFIG_PROTECT_MASK',
		          'PORTDIR', 'DISTDIR', 'PKGDIR', 'PORTAGE_TMPDIR',
		          'PORTDIR_OVERLAY', 'PORTAGE_BUNZIP2_COMMAND',
		          'PORTAGE_BZIP2_COMMAND',
		          'USE', 'CHOST', 'CFLAGS', 'CXXFLAGS',
		          'ACCEPT_KEYWORDS', 'ACCEPT_LICENSE', 'SYNC', 'SYNC_USER', 'SYNC_UMASK', 'FEATURES',
		          'EMERGE_DEFAULT_OPTS']

		myvars.extend(portage.util.grabfile(settings["PORTDIR"]+"/profiles/info_vars"))

	myvars_ignore_defaults = {
		'PORTAGE_BZIP2_COMMAND' : 'bzip2',
	}

	myvars = portage.util.unique_array(myvars)
	use_expand = settings.get('USE_EXPAND', '').split()
	use_expand.sort()
	unset_vars = []
	myvars.sort()
	for k in myvars:
		v = settings.get(k)
		if v is not None:
			if k != "USE":
				default = myvars_ignore_defaults.get(k)
				if default is not None and \
					default == v:
					continue
				append('%s="%s"' % (k, v))
			else:
				use = set(v.split())
				for varname in use_expand:
					flag_prefix = varname.lower() + "_"
					for f in list(use):
						if f.startswith(flag_prefix):
							use.remove(f)
				use = list(use)
				use.sort()
				use = ['USE="%s"' % " ".join(use)]
				for varname in use_expand:
					myval = settings.get(varname)
					if myval:
						use.append('%s="%s"' % (varname, myval))
				append(" ".join(use))
		else:
			unset_vars.append(k)
	if unset_vars:
		append("Unset:  "+", ".join(unset_vars))
	append("")
	append("")
	writemsg_stdout("\n".join(output_buffer),
		noiselevel=-1)

	# See if we can find any packages installed matching the strings
	# passed on the command line
	mypkgs = []
	eroot = settings['EROOT']
	vardb = trees[eroot]["vartree"].dbapi
	portdb = trees[eroot]['porttree'].dbapi
	bindb = trees[eroot]["bintree"].dbapi
	for x in myfiles:
		match_found = False
		installed_match = vardb.match(x)
		for installed in installed_match:
			mypkgs.append((installed, "installed"))
			match_found = True

		if match_found:
			continue

		for db, pkg_type in ((portdb, "ebuild"), (bindb, "binary")):
			if pkg_type == "binary" and "--usepkg" not in myopts:
				continue

			matches = db.match(x)
			matches.reverse()
			for match in matches:
				if pkg_type == "binary":
					if db.bintree.isremote(match):
						continue
				auxkeys = ["EAPI", "DEFINED_PHASES"]
				metadata = dict(zip(auxkeys, db.aux_get(match, auxkeys)))
				if metadata["EAPI"] not in ("0", "1", "2", "3") and \
					"info" in metadata["DEFINED_PHASES"].split():
					mypkgs.append((match, pkg_type))
					break

	# If some packages were found...
	if mypkgs:
		# Get our global settings (we only print stuff if it varies from
		# the current config)
		mydesiredvars = [ 'CHOST', 'CFLAGS', 'CXXFLAGS', 'LDFLAGS' ]
		auxkeys = mydesiredvars + list(vardb._aux_cache_keys)
		auxkeys.append('DEFINED_PHASES')
		pkgsettings = portage.config(clone=settings)

		# Loop through each package
		# Only print settings if they differ from global settings
		header_title = "Package Settings"
		print(header_width * "=")
		print(header_title.rjust(int(header_width/2 + len(header_title)/2)))
		print(header_width * "=")
		from portage.output import EOutput
		out = EOutput()
		for mypkg in mypkgs:
			cpv = mypkg[0]
			pkg_type = mypkg[1]
			# Get all package specific variables
			if pkg_type == "installed":
				metadata = dict(zip(auxkeys, vardb.aux_get(cpv, auxkeys)))
			elif pkg_type == "ebuild":
				metadata = dict(zip(auxkeys, portdb.aux_get(cpv, auxkeys)))
			elif pkg_type == "binary":
				metadata = dict(zip(auxkeys, bindb.aux_get(cpv, auxkeys)))

			pkg = Package(built=(pkg_type!="ebuild"), cpv=cpv,
				installed=(pkg_type=="installed"), metadata=zip(Package.metadata_keys,
				(metadata.get(x, '') for x in Package.metadata_keys)),
				root_config=root_config, type_name=pkg_type)

			if pkg_type == "installed":
				print("\n%s was built with the following:" % \
					colorize("INFORM", str(pkg.cpv)))
			elif pkg_type == "ebuild":
				print("\n%s would be build with the following:" % \
					colorize("INFORM", str(pkg.cpv)))
			elif pkg_type == "binary":
				print("\n%s (non-installed binary) was built with the following:" % \
					colorize("INFORM", str(pkg.cpv)))

			writemsg_stdout('%s\n' % pkg_use_display(pkg, myopts),
				noiselevel=-1)
			if pkg_type == "installed":
				for myvar in mydesiredvars:
					if metadata[myvar].split() != settings.get(myvar, '').split():
						print("%s=\"%s\"" % (myvar, metadata[myvar]))
			print()

			if metadata['DEFINED_PHASES']:
				if 'info' not in metadata['DEFINED_PHASES'].split():
					continue

			print(">>> Attempting to run pkg_info() for '%s'" % pkg.cpv)

			if pkg_type == "installed":
				ebuildpath = vardb.findname(pkg.cpv)
			elif pkg_type == "ebuild":
				ebuildpath = portdb.findname(pkg.cpv, myrepo=pkg.repo)
			elif pkg_type == "binary":
				tbz2_file = bindb.bintree.getname(pkg.cpv)
				ebuild_file_name = pkg.cpv.split("/")[1] + ".ebuild"
				ebuild_file_contents = portage.xpak.tbz2(tbz2_file).getfile(ebuild_file_name)
				tmpdir = tempfile.mkdtemp()
				ebuildpath = os.path.join(tmpdir, ebuild_file_name)
				file = open(ebuildpath, 'w')
				file.write(ebuild_file_contents)
				file.close()

			if not ebuildpath or not os.path.exists(ebuildpath):
				out.ewarn("No ebuild found for '%s'" % pkg.cpv)
				continue

			if pkg_type == "installed":
				portage.doebuild(ebuildpath, "info", settings=pkgsettings,
					debug=(settings.get("PORTAGE_DEBUG", "") == 1),
					mydbapi=trees[settings['EROOT']]["vartree"].dbapi,
					tree="vartree")
			elif pkg_type == "ebuild":
				portage.doebuild(ebuildpath, "info", settings=pkgsettings,
					debug=(settings.get("PORTAGE_DEBUG", "") == 1),
					mydbapi=trees[settings['EROOT']]['porttree'].dbapi,
					tree="porttree")
			elif pkg_type == "binary":
				portage.doebuild(ebuildpath, "info", settings=pkgsettings,
					debug=(settings.get("PORTAGE_DEBUG", "") == 1),
					mydbapi=trees[settings['EROOT']]["bintree"].dbapi,
					tree="bintree")
				shutil.rmtree(tmpdir)

def action_metadata(settings, portdb, myopts, porttrees=None):
	if porttrees is None:
		porttrees = portdb.porttrees
	portage.writemsg_stdout("\n>>> Updating Portage cache\n")
	old_umask = os.umask(0o002)
	cachedir = os.path.normpath(settings.depcachedir)
	if cachedir in ["/",    "/bin", "/dev",  "/etc",  "/home",
					"/lib", "/opt", "/proc", "/root", "/sbin",
					"/sys", "/tmp", "/usr",  "/var"]:
		print("!!! PORTAGE_DEPCACHEDIR IS SET TO A PRIMARY " + \
			"ROOT DIRECTORY ON YOUR SYSTEM.", file=sys.stderr)
		print("!!! This is ALMOST CERTAINLY NOT what you want: '%s'" % cachedir, file=sys.stderr)
		sys.exit(73)
	if not os.path.exists(cachedir):
		os.makedirs(cachedir)

	auxdbkeys = portdb._known_keys

	class TreeData(object):
		__slots__ = ('dest_db', 'eclass_db', 'path', 'src_db', 'valid_nodes')
		def __init__(self, dest_db, eclass_db, path, src_db):
			self.dest_db = dest_db
			self.eclass_db = eclass_db
			self.path = path
			self.src_db = src_db
			self.valid_nodes = set()

	porttrees_data = []
	for path in porttrees:
		src_db = portdb._pregen_auxdb.get(path)
		if src_db is None:
			# portdbapi does not populate _pregen_auxdb
			# when FEATURES=metadata-transfer is enabled
			src_db = portdb._create_pregen_cache(path)

		if src_db is not None:
			porttrees_data.append(TreeData(portdb.auxdb[path],
				portdb._repo_info[path].eclass_db, path, src_db))

	porttrees = [tree_data.path for tree_data in porttrees_data]

	quiet = settings.get('TERM') == 'dumb' or \
		'--quiet' in myopts or \
		not sys.stdout.isatty()

	onProgress = None
	if not quiet:
		progressBar = portage.output.TermProgressBar()
		progressHandler = ProgressHandler()
		onProgress = progressHandler.onProgress
		def display():
			progressBar.set(progressHandler.curval, progressHandler.maxval)
		progressHandler.display = display
		def sigwinch_handler(signum, frame):
			lines, progressBar.term_columns = \
				portage.output.get_term_size()
		signal.signal(signal.SIGWINCH, sigwinch_handler)

	# Temporarily override portdb.porttrees so portdb.cp_all()
	# will only return the relevant subset.
	portdb_porttrees = portdb.porttrees
	portdb.porttrees = porttrees
	try:
		cp_all = portdb.cp_all()
	finally:
		portdb.porttrees = portdb_porttrees

	curval = 0
	maxval = len(cp_all)
	if onProgress is not None:
		onProgress(maxval, curval)

	from portage import eapi_is_supported, \
		_validate_cache_for_unsupported_eapis

	# TODO: Display error messages, but do not interfere with the progress bar.
	# Here's how:
	#  1) erase the progress bar
	#  2) show the error message
	#  3) redraw the progress bar on a new line

	for cp in cp_all:
		for tree_data in porttrees_data:

			src_chf = tree_data.src_db.validation_chf
			dest_chf = tree_data.dest_db.validation_chf
			dest_chf_key = '_%s_' % dest_chf
			dest_chf_getter = operator.attrgetter(dest_chf)

			for cpv in portdb.cp_list(cp, mytree=tree_data.path):
				tree_data.valid_nodes.add(cpv)
				try:
					src = tree_data.src_db[cpv]
				except (CacheError, KeyError):
					continue

				ebuild_location = portdb.findname(cpv, mytree=tree_data.path)
				if ebuild_location is None:
					continue
				ebuild_hash = hashed_path(ebuild_location)

				try:
					if not tree_data.src_db.validate_entry(src,
						ebuild_hash, tree_data.eclass_db):
						continue
				except CacheError:
					continue

				eapi = src.get('EAPI')
				if not eapi:
					eapi = '0'
				eapi = eapi.lstrip('-')
				eapi_supported = eapi_is_supported(eapi)
				if not eapi_supported:
					if not _validate_cache_for_unsupported_eapis:
						continue

				dest = None
				try:
					dest = tree_data.dest_db[cpv]
				except (KeyError, CacheError):
					pass

				for d in (src, dest):
					if d is not None and d.get('EAPI') in ('', '0'):
						del d['EAPI']

				if src_chf != 'mtime':
					# src may contain an irrelevant _mtime_ which corresponds
					# to the time that the cache entry was written
					src.pop('_mtime_', None)

				if src_chf != dest_chf:
					# populate src entry with dest_chf_key
					# (the validity of the dest_chf that we generate from the
					# ebuild here relies on the fact that we already used
					# validate_entry to validate the ebuild with src_chf)
					src[dest_chf_key] = dest_chf_getter(ebuild_hash)

				if dest is not None:
					if not (dest[dest_chf_key] == src[dest_chf_key] and \
						tree_data.eclass_db.validate_and_rewrite_cache(
							dest['_eclasses_'], tree_data.dest_db.validation_chf,
							tree_data.dest_db.store_eclass_paths) is not None and \
						set(dest['_eclasses_']) == set(src['_eclasses_'])):
						dest = None
					else:
						# We don't want to skip the write unless we're really
						# sure that the existing cache is identical, so don't
						# trust _mtime_ and _eclasses_ alone.
						for k in auxdbkeys:
							if dest.get(k, '') != src.get(k, ''):
								dest = None
								break

				if dest is not None:
					# The existing data is valid and identical,
					# so there's no need to overwrite it.
					continue

				if not eapi_supported:
					src = {
						'EAPI'       : '-' + eapi,
						dest_chf_key : src[dest_chf_key],
						'_eclasses_' : src['_eclasses_'],
					}

				try:
					tree_data.dest_db[cpv] = src
				except CacheError:
					# ignore it; can't do anything about it.
					pass

		curval += 1
		if onProgress is not None:
			onProgress(maxval, curval)

	if onProgress is not None:
		onProgress(maxval, curval)

	for tree_data in porttrees_data:
		try:
			dead_nodes = set(tree_data.dest_db)
		except CacheError as e:
			writemsg_level("Error listing cache entries for " + \
				"'%s': %s, continuing...\n" % (tree_data.path, e),
				level=logging.ERROR, noiselevel=-1)
			del e
		else:
			dead_nodes.difference_update(tree_data.valid_nodes)
			for cpv in dead_nodes:
				try:
					del tree_data.dest_db[cpv]
				except (KeyError, CacheError):
					pass

	if not quiet:
		# make sure the final progress is displayed
		progressHandler.display()
		print()
		signal.signal(signal.SIGWINCH, signal.SIG_DFL)

	sys.stdout.flush()
	os.umask(old_umask)

def action_regen(settings, portdb, max_jobs, max_load):
	xterm_titles = "notitles" not in settings.features
	emergelog(xterm_titles, " === regen")
	#regenerate cache entries
	sys.stdout.flush()

	regen = MetadataRegen(portdb, max_jobs=max_jobs, max_load=max_load)
	received_signal = []

	def emergeexitsig(signum, frame):
		signal.signal(signal.SIGINT, signal.SIG_IGN)
		signal.signal(signal.SIGTERM, signal.SIG_IGN)
		portage.util.writemsg("\n\nExiting on signal %(signal)s\n" % \
			{"signal":signum})
		regen.terminate()
		received_signal.append(128 + signum)

	earlier_sigint_handler = signal.signal(signal.SIGINT, emergeexitsig)
	earlier_sigterm_handler = signal.signal(signal.SIGTERM, emergeexitsig)

	try:
		regen.run()
	finally:
		# Restore previous handlers
		if earlier_sigint_handler is not None:
			signal.signal(signal.SIGINT, earlier_sigint_handler)
		else:
			signal.signal(signal.SIGINT, signal.SIG_DFL)
		if earlier_sigterm_handler is not None:
			signal.signal(signal.SIGTERM, earlier_sigterm_handler)
		else:
			signal.signal(signal.SIGTERM, signal.SIG_DFL)

	if received_signal:
		sys.exit(received_signal[0])

	portage.writemsg_stdout("done!\n")
	return regen.returncode

def action_search(root_config, myopts, myfiles, spinner):
	if not myfiles:
		print("emerge: no search terms provided.")
	else:
		searchinstance = search(root_config,
			spinner, "--searchdesc" in myopts,
			"--quiet" not in myopts, "--usepkg" in myopts,
			"--usepkgonly" in myopts)
		for mysearch in myfiles:
			try:
				searchinstance.execute(mysearch)
			except re.error as comment:
				print("\n!!! Regular expression error in \"%s\": %s" % ( mysearch, comment ))
				sys.exit(1)
			searchinstance.output()

def action_sync(settings, trees, mtimedb, myopts, myaction):
	enter_invalid = '--ask-enter-invalid' in myopts
	xterm_titles = "notitles" not in settings.features
	emergelog(xterm_titles, " === sync")
	portdb = trees[settings['EROOT']]['porttree'].dbapi
	myportdir = portdb.porttree_root
	if not myportdir:
		myportdir = settings.get('PORTDIR', '')
		if myportdir and myportdir.strip():
			myportdir = os.path.realpath(myportdir)
		else:
			myportdir = None
	out = portage.output.EOutput()
	global_config_path = GLOBAL_CONFIG_PATH
	if settings['EPREFIX']:
		global_config_path = os.path.join(settings['EPREFIX'],
				GLOBAL_CONFIG_PATH.lstrip(os.sep))
	if not myportdir:
		sys.stderr.write("!!! PORTDIR is undefined. Is %s/make.globals missing?\n" % global_config_path)
		sys.exit(1)
	if myportdir[-1]=="/":
		myportdir=myportdir[:-1]
	try:
		st = os.stat(myportdir)
	except OSError:
		st = None

	syncuri = settings.get("SYNC", "").strip()
	syncuser = settings.get("SYNC_USER", "root").strip()
	syncumask = settings.get("SYNC_UMASK", "022").strip()
	updatecache_flg = False
	if myaction == "metadata":
		print("skipping sync")
		updatecache_flg = True

	if portage.process.find_binary("git") is None:
		msg = ["Command not found: git", "Type \"emerge dev-vcs/git\" to enable git support."]
		for l in msg:
			writemsg_level("!!! %s\n" % l, level=logging.ERROR, noiselevel=-1)
		return 1
	updatecache_flg = True
	if not os.path.exists(myportdir):
		if not syncuri:
			writemsg_level("SYNC is undefined.\nPlease set SYNC to the remote location of the Portage repository.\n", noiselevel=-1, level=logging.ERROR)
	elif ".git" in vcs_dirs:
		# Update existing git repository, and ignore the syncuri. We are
		# going to trust the user and assume that the user is in the branch
		# that he/she wants updated. We'll let the user manage branches with
		# git directly.
		if portage.process.find_binary("git") is None:
			msg = ["Command not found: git",
			"Type \"emerge dev-util/git\" to enable git support."]
			for l in msg:
				writemsg_level("!!! %s\n" % l,
					level=logging.ERROR, noiselevel=-1)
			return 1
		msg = ">>> Starting git pull in %s..." % myportdir
		emergelog(xterm_titles, msg )
		writemsg_level(msg + "\n")
		exitcode = portage.process.spawn_bash("cd %s ; git pull" % \
			(portage._shell_quote(myportdir),), **spawn_kwargs)
		if exitcode != os.EX_OK:
			msg = "!!! git pull error in %s." % myportdir
			emergelog(xterm_titles, msg)
			writemsg_level(msg + "\n", level=logging.ERROR, noiselevel=-1)
			return exitcode
		msg = ">>> Git pull in %s successful" % myportdir
		emergelog(xterm_titles, msg)
		writemsg_level(msg + "\n")
		exitcode = git_sync_timestamps(portdb, myportdir)
		if exitcode == os.EX_OK:
			updatecache_flg = True
	elif syncuri[:8]=="rsync://" or syncuri[:6]=="ssh://":
		for vcs_dir in vcs_dirs:
			writemsg_level(("!!! %s appears to be under revision " + \
				"control (contains %s).\n!!! Aborting rsync sync.\n") % \
				(myportdir, vcs_dir), level=logging.ERROR, noiselevel=-1)
			return 1


		# A few tricks are required to get git cloning by a non-root user. We will create a temporary working directory called work_path
		# (/usr/portage.sync). We will make sure this directory is owned by the SYNC_USER user, and then we will use "su" to run git clone
		# inside this directory, so that git can create the initial repository directory with the proper user permissiosn. After git
		# clone completes, we will move our new portage tree in repo_path_tmp to repo_path_fin, its final location. And then we will remove
		# work_path, our temporary directory.

		# common_path = /usr
		# repo_dir = portage
		# work_path = /usr/portage.sync
		# repo_path_tmp = /usr/portage.sync/portage
		# repo_path_fin = /usr/portage

		common_path = os.path.dirname(myportdir)
		repo_dir = os.path.basename(myportdir)
		work_path = os.path.join(common_path, repo_dir + ".sync")
		repo_path_tmp = os.path.join(work_path, repo_dir)
		repo_path_fin = os.path.join(common_path, repo_dir)
			
		print(">>> Using %s as temporary clone directory..." % repo_path_tmp)

		# if the directories we will be using exist, try to remove them, non-recursively. If that doesn't work, there are files in them
		# and throw an error message, requesting the user remove these files so that sync can proceed.

		for checkdir in [ repo_path_tmp, work_path ]:
			if os.path.exists(checkdir):
				try:
					os.rmdir(checkdir)
				except OSError as e:
					print("!!! %s exists and contains files. Please remove so that clone can proceed." % checkdir )
					sys.exit(1)

		# at this point, we want to create an initial portage.sync directory, owned by the user, into which we can use su to run git as
		# the user, and create the new portage tree directory owned by the user.

		if not os.path.exists(common_path):
			# create common path directory, ie. /var/git, if it doesn't exist.
			os.makedirs(common_path)

		if portage.process.spawn_bash("cd %s && umask %s && install -d -o %s %s" % ( common_path, syncumask, syncuser, work_path)) != os.EX_OK:
			print("!!! Unable to create initial sync directory %s; exiting." % work_path)
			sys.exit(1)

		# We've created our temporary work directory, but is the final location actually reachable - ie. readable, by SYNC_USER? We'll
		# find out now.

		if portage.process.spawn_bash("su - %s -s /bin/sh -c 'cd %s'" % ( syncuser, common_path )) != os.EX_OK:
			print("!!! Path %s is not reachable by user %s; please adjust permissions or SYNC_USER setting to correct." %  ( common_path, syncuser ))
			sys.exit(1)

		# Everything looks OK, so now we will clone the repository:
		
		print(">>> Starting initial git clone with "+syncuri+"...")

		if portage.process.spawn_bash("su - %s -s /bin/sh -c 'umask %s && cd %s && exec git clone %s %s && mv '" % (syncuser, syncumask, work_path, portage._shell_quote(syncuri), repo_dir)) != os.EX_OK:
			print("!!! git clone error; exiting.")
			sys.exit(1)
		
		# Our clone should now exist in the temporary location, now move it to the final location, as root:

		if portage.process.spawn_bash("mv %s %s" % (repo_path_tmp, repo_path_fin)) != os.EX_OK:
			print("!!! Couldn't move %s into final location %s; exiting." % ( repo_path_tmp, repo_path_fin ))
			sys.exit(1)

		# Clean up after ourselves:
		portage.process.spawn_bash("rm -rf %s" % (repo_path_tmp))
	else:
		if not os.path.exists(myportdir+"/.git"):
			print("!!! Portage tree at %s does not appear to be a git repository. Please move out of the way or correct your PORTDIR setting and retry." % myportdir)
			sys.exit(1)
		if portage.process.spawn_bash("su - %s -s /bin/sh -c 'cd %s >/dev/null 2>&1'" % ( syncuser, myportdir )) != os.EX_OK:
			print("!!! Portage tree at %s is not reachable by user %s; please adjust permissions to correct." %  ( myportdir, syncuser ))
			sys.exit(1)
		print(">>> Starting git pull...")
		exitcode = portage.process.spawn_bash( "su - %s -s /bin/sh -c 'umask %s && cd %s && exec git pull --no-stat'" % (syncuser, syncumask, portage._shell_quote(myportdir),))
		if exitcode != os.EX_OK:
			msg = "!!! git pull error in %s." % myportdir
			emergelog(xterm_titles, msg)
			writemsg_level(msg + "\n", level=logging.ERROR, noiselevel=-1)
			return exitcode
		msg = ">>> Git pull in %s successful" % myportdir
		emergelog(xterm_titles, msg)
		writemsg_level(msg + "\n")

	# if initial clone or sync, 
	exitcode = git_sync_timestamps(settings, myportdir)
	if exitcode != os.EX_OK:
		sys.exit(retval)

	if updatecache_flg and myaction != "metadata" and "metadata-transfer" not in settings.features:
		updatecache_flg = False

	# Reload the whole config from scratch.
	settings, trees, mtimedb = load_emerge_config(trees=trees)
	adjust_configs(myopts, trees)
	root_config = trees[settings['EROOT']]['root_config']
	portdb = trees[settings['EROOT']]['porttree'].dbapi

	if updatecache_flg and os.path.exists(os.path.join(myportdir, 'metadata', 'cache')):

		# Only update cache for myportdir since that's
		# the only one that's been synced here.
		action_metadata(settings, portdb, myopts, porttrees=[myportdir])

	if myopts.get('--package-moves') != 'n' and _global_updates(trees, mtimedb["updates"], quiet=("--quiet" in myopts)):
		mtimedb.commit()
		# Reload the whole config from scratch.
		settings, trees, mtimedb = load_emerge_config(trees=trees)
		adjust_configs(myopts, trees)
		portdb = trees[settings['EROOT']]['porttree'].dbapi
		root_config = trees[settings['EROOT']]['root_config']

	chk_updated_cfg_files(settings["EROOT"], portage.util.shlex_split(settings.get("CONFIG_PROTECT", "")))
	mybestpv = portdb.xmatch("bestmatch-visible",
		portage.const.PORTAGE_PACKAGE_ATOM)
	mypvs = portage.best(
		trees[settings['EROOT']]['vartree'].dbapi.match(
		portage.const.PORTAGE_PACKAGE_ATOM))

	chk_updated_cfg_files(settings["EROOT"],
		portage.util.shlex_split(settings.get("CONFIG_PROTECT", "")))

	if myaction != "metadata":
		postsync = os.path.join(settings["PORTAGE_CONFIGROOT"], portage.USER_CONFIG_PATH, "bin", "post_sync")
		if os.access(postsync, os.X_OK):
			retval = portage.process.spawn( [postsync, syncuri], env=settings.environ())
			if retval != os.EX_OK:
				print(red(" * ") + bold("spawn failed of " + postsync))

	display_news_notification(root_config, myopts)
	return os.EX_OK

def action_uninstall(settings, trees, ldpath_mtimes,
	opts, action, files, spinner):

	# For backward compat, some actions do not require leading '='.
	ignore_missing_eq = action in ('clean', 'unmerge')
	root = settings['ROOT']
	vardb = trees[root]['vartree'].dbapi
	valid_atoms = []
	lookup_owners = []

	# Ensure atoms are valid before calling unmerge().
	# For backward compat, leading '=' is not required.
	for x in files:
		if is_valid_package_atom(x, allow_repo=True) or \
			(ignore_missing_eq and is_valid_package_atom('=' + x)):

			try:
				valid_atoms.append(
					dep_expand(x, mydb=vardb, settings=settings))
			except portage.exception.AmbiguousPackageName as e:
				msg = "The short ebuild name \"" + x + \
					"\" is ambiguous.  Please specify " + \
					"one of the following " + \
					"fully-qualified ebuild names instead:"
				for line in textwrap.wrap(msg, 70):
					writemsg_level("!!! %s\n" % (line,),
						level=logging.ERROR, noiselevel=-1)
				for i in e.args[0]:
					writemsg_level("    %s\n" % colorize("INFORM", i),
						level=logging.ERROR, noiselevel=-1)
				writemsg_level("\n", level=logging.ERROR, noiselevel=-1)
				return 1

		elif x.startswith(os.sep):
			if not x.startswith(root):
				writemsg_level(("!!! '%s' does not start with" + \
					" $ROOT.\n") % x, level=logging.ERROR, noiselevel=-1)
				return 1
			# Queue these up since it's most efficient to handle
			# multiple files in a single iter_owners() call.
			lookup_owners.append(x)

		elif x.startswith(SETPREFIX) and action == "deselect":
			valid_atoms.append(x)

		else:
			msg = []
			msg.append("'%s' is not a valid package atom." % (x,))
			msg.append("Please check ebuild(5) for full details.")
			writemsg_level("".join("!!! %s\n" % line for line in msg),
				level=logging.ERROR, noiselevel=-1)
			return 1

	if lookup_owners:
		relative_paths = []
		search_for_multiple = False
		if len(lookup_owners) > 1:
			search_for_multiple = True

		for x in lookup_owners:
			if not search_for_multiple and os.path.isdir(x):
				search_for_multiple = True
			relative_paths.append(x[len(root)-1:])

		owners = set()
		for pkg, relative_path in \
			vardb._owners.iter_owners(relative_paths):
			owners.add(pkg.mycpv)
			if not search_for_multiple:
				break

		if owners:
			for cpv in owners:
				slot = vardb.aux_get(cpv, ['SLOT'])[0]
				if not slot:
					# portage now masks packages with missing slot, but it's
					# possible that one was installed by an older version
					atom = portage.cpv_getkey(cpv)
				else:
					atom = '%s:%s' % (portage.cpv_getkey(cpv), slot)
				valid_atoms.append(portage.dep.Atom(atom))
		else:
			writemsg_level(("!!! '%s' is not claimed " + \
				"by any package.\n") % lookup_owners[0],
				level=logging.WARNING, noiselevel=-1)

	if files and not valid_atoms:
		return 1

	if action == 'unmerge' and \
		'--quiet' not in opts and \
		'--quiet-unmerge-warn' not in opts:
		msg = "This action can remove important packages! " + \
			"In order to be safer, use " + \
			"`emerge -pv --depclean <atom>` to check for " + \
			"reverse dependencies before removing packages."
		out = portage.output.EOutput()
		for line in textwrap.wrap(msg, 72):
			out.ewarn(line)

	if action == 'deselect':
		return action_deselect(settings, trees, opts, valid_atoms)

	# Create a Scheduler for calls to unmerge(), in order to cause
	# redirection of ebuild phase output to logs as required for
	# options such as --quiet.
	sched = Scheduler(settings, trees, None, opts,
		spinner)
	sched._background = sched._background_mode()
	sched._status_display.quiet = True

	if action in ('clean', 'unmerge') or \
		(action == 'prune' and "--nodeps" in opts):
		# When given a list of atoms, unmerge them in the order given.
		ordered = action == 'unmerge'
		unmerge(trees[settings["ROOT"]]['root_config'], opts, action,
			valid_atoms, ldpath_mtimes, ordered=ordered,
			scheduler=sched._sched_iface)
		rval = os.EX_OK
	else:
		rval = action_depclean(settings, trees, ldpath_mtimes,
			opts, action, valid_atoms, spinner, scheduler=sched._sched_iface)

	return rval




def action_uninstall(settings, trees, ldpath_mtimes,
	opts, action, files, spinner):
	# For backward compat, some actions do not require leading '='.
	ignore_missing_eq = action in ('clean', 'unmerge')
	root = settings['ROOT']
	eroot = settings['EROOT']
	vardb = trees[settings['EROOT']]['vartree'].dbapi
	valid_atoms = []
	lookup_owners = []

	# Ensure atoms are valid before calling unmerge().
	# For backward compat, leading '=' is not required.
	for x in files:
		if is_valid_package_atom(x, allow_repo=True) or \
			(ignore_missing_eq and is_valid_package_atom('=' + x)):

			try:
				atom = dep_expand(x, mydb=vardb, settings=settings)
			except portage.exception.AmbiguousPackageName as e:
				msg = "The short ebuild name \"" + x + \
					"\" is ambiguous.  Please specify " + \
					"one of the following " + \
					"fully-qualified ebuild names instead:"
				for line in textwrap.wrap(msg, 70):
					writemsg_level("!!! %s\n" % (line,),
						level=logging.ERROR, noiselevel=-1)
				for i in e.args[0]:
					writemsg_level("    %s\n" % colorize("INFORM", i),
						level=logging.ERROR, noiselevel=-1)
				writemsg_level("\n", level=logging.ERROR, noiselevel=-1)
				return 1
			else:
				if atom.use and atom.use.conditional:
					writemsg_level(
						("\n\n!!! '%s' contains a conditional " + \
						"which is not allowed.\n") % (x,),
						level=logging.ERROR, noiselevel=-1)
					writemsg_level(
						"!!! Please check ebuild(5) for full details.\n",
						level=logging.ERROR)
					return 1
				valid_atoms.append(atom)

		elif x.startswith(os.sep):
			if not x.startswith(eroot):
				writemsg_level(("!!! '%s' does not start with" + \
					" $EROOT.\n") % x, level=logging.ERROR, noiselevel=-1)
				return 1
			# Queue these up since it's most efficient to handle
			# multiple files in a single iter_owners() call.
			lookup_owners.append(x)

		elif x.startswith(SETPREFIX) and action == "deselect":
			valid_atoms.append(x)

		elif "*" in x:
			try:
				ext_atom = Atom(x, allow_repo=True, allow_wildcard=True)
			except InvalidAtom:
				msg = []
				msg.append("'%s' is not a valid package atom." % (x,))
				msg.append("Please check ebuild(5) for full details.")
				writemsg_level("".join("!!! %s\n" % line for line in msg),
					level=logging.ERROR, noiselevel=-1)
				return 1

			for cp in vardb.cp_all():
				if extended_cp_match(ext_atom.cp, cp):
					atom = cp
					if ext_atom.slot:
						atom += ":" + ext_atom.slot
					if ext_atom.repo:
						atom += "::" + ext_atom.repo

					if vardb.match(atom):
						valid_atoms.append(Atom(atom, allow_repo=True))

		else:
			msg = []
			msg.append("'%s' is not a valid package atom." % (x,))
			msg.append("Please check ebuild(5) for full details.")
			writemsg_level("".join("!!! %s\n" % line for line in msg),
				level=logging.ERROR, noiselevel=-1)
			return 1

	if lookup_owners:
		relative_paths = []
		search_for_multiple = False
		if len(lookup_owners) > 1:
			search_for_multiple = True

		for x in lookup_owners:
			if not search_for_multiple and os.path.isdir(x):
				search_for_multiple = True
			relative_paths.append(x[len(root)-1:])

		owners = set()
		for pkg, relative_path in \
			vardb._owners.iter_owners(relative_paths):
			owners.add(pkg.mycpv)
			if not search_for_multiple:
				break

		if owners:
			for cpv in owners:
				slot = vardb.aux_get(cpv, ['SLOT'])[0]
				if not slot:
					# portage now masks packages with missing slot, but it's
					# possible that one was installed by an older version
					atom = portage.cpv_getkey(cpv)
				else:
					atom = '%s:%s' % (portage.cpv_getkey(cpv), slot)
				valid_atoms.append(portage.dep.Atom(atom))
		else:
			writemsg_level(("!!! '%s' is not claimed " + \
				"by any package.\n") % lookup_owners[0],
				level=logging.WARNING, noiselevel=-1)

	if files and not valid_atoms:
		return 1

	if action == 'unmerge' and \
		'--quiet' not in opts and \
		'--quiet-unmerge-warn' not in opts:
		msg = "This action can remove important packages! " + \
			"In order to be safer, use " + \
			"`emerge -pv --depclean <atom>` to check for " + \
			"reverse dependencies before removing packages."
		out = portage.output.EOutput()
		for line in textwrap.wrap(msg, 72):
			out.ewarn(line)

	if action == 'deselect':
		return action_deselect(settings, trees, opts, valid_atoms)

	# Create a Scheduler for calls to unmerge(), in order to cause
	# redirection of ebuild phase output to logs as required for
	# options such as --quiet.
	sched = Scheduler(settings, trees, None, opts,
		spinner)
	sched._background = sched._background_mode()
	sched._status_display.quiet = True

	if sched._background:
		sched.settings.unlock()
		sched.settings["PORTAGE_BACKGROUND"] = "1"
		sched.settings.backup_changes("PORTAGE_BACKGROUND")
		sched.settings.lock()
		sched.pkgsettings[eroot] = portage.config(clone=sched.settings)

	if action in ('clean', 'unmerge') or \
		(action == 'prune' and "--nodeps" in opts):
		# When given a list of atoms, unmerge them in the order given.
		ordered = action == 'unmerge'
		unmerge(trees[settings['EROOT']]['root_config'], opts, action,
			valid_atoms, ldpath_mtimes, ordered=ordered,
			scheduler=sched._sched_iface)
		rval = os.EX_OK
	else:
		rval = action_depclean(settings, trees, ldpath_mtimes,
			opts, action, valid_atoms, spinner, scheduler=sched._sched_iface)

	return rval

def adjust_configs(myopts, trees):
	for myroot in trees:
		mysettings =  trees[myroot]["vartree"].settings
		mysettings.unlock()
		adjust_config(myopts, mysettings)
		mysettings.lock()

def adjust_config(myopts, settings):
	"""Make emerge specific adjustments to the config."""

	# Kill noauto as it will break merges otherwise.
	if "noauto" in settings.features:
		settings.features.remove('noauto')

	fail_clean = myopts.get('--fail-clean')
	if fail_clean is not None:
		if fail_clean is True and \
			'fail-clean' not in settings.features:
			settings.features.add('fail-clean')
		elif fail_clean == 'n' and \
			'fail-clean' in settings.features:
			settings.features.remove('fail-clean')

	CLEAN_DELAY = 5
	try:
		CLEAN_DELAY = int(settings.get("CLEAN_DELAY", str(CLEAN_DELAY)))
	except ValueError as e:
		portage.writemsg("!!! %s\n" % str(e), noiselevel=-1)
		portage.writemsg("!!! Unable to parse integer: CLEAN_DELAY='%s'\n" % \
			settings["CLEAN_DELAY"], noiselevel=-1)
	settings["CLEAN_DELAY"] = str(CLEAN_DELAY)
	settings.backup_changes("CLEAN_DELAY")

	EMERGE_WARNING_DELAY = 10
	try:
		EMERGE_WARNING_DELAY = int(settings.get(
			"EMERGE_WARNING_DELAY", str(EMERGE_WARNING_DELAY)))
	except ValueError as e:
		portage.writemsg("!!! %s\n" % str(e), noiselevel=-1)
		portage.writemsg("!!! Unable to parse integer: EMERGE_WARNING_DELAY='%s'\n" % \
			settings["EMERGE_WARNING_DELAY"], noiselevel=-1)
	settings["EMERGE_WARNING_DELAY"] = str(EMERGE_WARNING_DELAY)
	settings.backup_changes("EMERGE_WARNING_DELAY")

	if "--buildpkg" in myopts:
		settings.features.add("buildpkg")

	if "--quiet" in myopts or "--quiet-build" in myopts:
		settings["PORTAGE_QUIET"]="1"
		settings.backup_changes("PORTAGE_QUIET")

	if "--verbose" in myopts:
		settings["PORTAGE_VERBOSE"] = "1"
		settings.backup_changes("PORTAGE_VERBOSE")

	# Set so that configs will be merged regardless of remembered status
	if ("--noconfmem" in myopts):
		settings["NOCONFMEM"]="1"
		settings.backup_changes("NOCONFMEM")

	# Set various debug markers... They should be merged somehow.
	PORTAGE_DEBUG = 0
	try:
		PORTAGE_DEBUG = int(settings.get("PORTAGE_DEBUG", str(PORTAGE_DEBUG)))
		if PORTAGE_DEBUG not in (0, 1):
			portage.writemsg("!!! Invalid value: PORTAGE_DEBUG='%i'\n" % \
				PORTAGE_DEBUG, noiselevel=-1)
			portage.writemsg("!!! PORTAGE_DEBUG must be either 0 or 1\n",
				noiselevel=-1)
			PORTAGE_DEBUG = 0
	except ValueError as e:
		portage.writemsg("!!! %s\n" % str(e), noiselevel=-1)
		portage.writemsg("!!! Unable to parse integer: PORTAGE_DEBUG='%s'\n" %\
			settings["PORTAGE_DEBUG"], noiselevel=-1)
		del e
	if "--debug" in myopts:
		PORTAGE_DEBUG = 1
	settings["PORTAGE_DEBUG"] = str(PORTAGE_DEBUG)
	settings.backup_changes("PORTAGE_DEBUG")

	if settings.get("NOCOLOR") not in ("yes","true"):
		portage.output.havecolor = 1

	"""The explicit --color < y | n > option overrides the NOCOLOR environment
	variable and stdout auto-detection."""
	if "--color" in myopts:
		if "y" == myopts["--color"]:
			portage.output.havecolor = 1
			settings["NOCOLOR"] = "false"
		else:
			portage.output.havecolor = 0
			settings["NOCOLOR"] = "true"
		settings.backup_changes("NOCOLOR")
	elif settings.get('TERM') == 'dumb' or \
		not sys.stdout.isatty():
		portage.output.havecolor = 0
		settings["NOCOLOR"] = "true"
		settings.backup_changes("NOCOLOR")

def display_missing_pkg_set(root_config, set_name):

	msg = []
	msg.append(("emerge: There are no sets to satisfy '%s'. " + \
		"The following sets exist:") % \
		colorize("INFORM", set_name))
	msg.append("")

	for s in sorted(root_config.sets):
		msg.append("    %s" % s)
	msg.append("")

	writemsg_level("".join("%s\n" % l for l in msg),
		level=logging.ERROR, noiselevel=-1)

def relative_profile_path(portdir, abs_profile):
	realpath = os.path.realpath(abs_profile)
	basepath   = os.path.realpath(os.path.join(portdir, "profiles"))
	if realpath.startswith(basepath):
		profilever = realpath[1 + len(basepath):]
	else:
		profilever = None
	return profilever

def getportageversion(portdir, _unused, profile, chost, vardb):
	profilever = None
	if profile:
		profilever = relative_profile_path(portdir, profile)
		if profilever is None:
			try:
				for parent in portage.grabfile(
					os.path.join(profile, 'parent')):
					profilever = relative_profile_path(portdir,
						os.path.join(profile, parent))
					if profilever is not None:
						break
			except portage.exception.PortageException:
				pass

			if profilever is None:
				try:
					profilever = "!" + os.readlink(profile)
				except (OSError):
					pass

	if profilever is None:
		profilever = "unavailable"

	libcver = []
	libclist = set()
	for atom in expand_new_virt(vardb, portage.const.LIBC_PACKAGE_ATOM):
		if not atom.blocker:
			libclist.update(vardb.match(atom))
	if libclist:
		for cpv in sorted(libclist):
			libc_split = portage.catpkgsplit(cpv)[1:]
			if libc_split[-1] == "r0":
				libc_split[:-1]
			libcver.append("-".join(libc_split))
	else:
		libcver = ["unavailable"]

	gccver = getgccversion(chost)
	unameout=platform.release()+" "+platform.machine()

	return "Portage %s (%s, %s, %s, %s)" % \
		(portage.VERSION, profilever, gccver, ",".join(libcver), unameout)

def git_sync_timestamps(portdb, portdir):
	"""
	Since git doesn't preserve timestamps, synchronize timestamps between
	entries and ebuilds/eclasses. Assume the cache has the correct timestamp
	for a given file as long as the file in the working tree is not modified
	(relative to HEAD).
	"""

	cache_db = portdb._pregen_auxdb.get(portdir)

	try:
		if cache_db is None:
			# portdbapi does not populate _pregen_auxdb
			# when FEATURES=metadata-transfer is enabled
			cache_db = portdb._create_pregen_cache(portdir)
	except CacheError as e:
		writemsg_level("!!! Unable to instantiate cache: %s\n" % (e,),
			level=logging.ERROR, noiselevel=-1)
		return 1

	if cache_db is None:
		return os.EX_OK

	if cache_db.validation_chf != 'mtime':
		# newer formats like md5-dict do not require mtime sync
		return os.EX_OK

	writemsg_level(">>> Synchronizing timestamps...\n")

	ec_dir = os.path.join(portdir, "eclass")
	try:
		ec_names = set(f[:-7] for f in os.listdir(ec_dir) \
			if f.endswith(".eclass"))
	except OSError as e:
		writemsg_level("!!! Unable to list eclasses: %s\n" % (e,),
			level=logging.ERROR, noiselevel=-1)
		return 1

	args = [portage.const.BASH_BINARY, "-c",
		"cd %s && git diff-index --name-only --diff-filter=M HEAD" % \
		portage._shell_quote(portdir)]
	proc = subprocess.Popen(args, stdout=subprocess.PIPE)
	modified_files = set(_unicode_decode(l).rstrip("\n") for l in proc.stdout)
	rval = proc.wait()
	proc.stdout.close()
	if rval != os.EX_OK:
		return rval

	modified_eclasses = set(ec for ec in ec_names \
		if os.path.join("eclass", ec + ".eclass") in modified_files)

	updated_ec_mtimes = {}

	for cpv in cache_db:
		cpv_split = portage.catpkgsplit(cpv)
		if cpv_split is None:
			writemsg_level("!!! Invalid cache entry: %s\n" % (cpv,),
				level=logging.ERROR, noiselevel=-1)
			continue

		cat, pn, ver, rev = cpv_split
		cat, pf = portage.catsplit(cpv)
		relative_eb_path = os.path.join(cat, pn, pf + ".ebuild")
		if relative_eb_path in modified_files:
			continue

		try:
			cache_entry = cache_db[cpv]
			eb_mtime = cache_entry.get("_mtime_")
			ec_mtimes = cache_entry.get("_eclasses_")
		except KeyError:
			writemsg_level("!!! Missing cache entry: %s\n" % (cpv,),
				level=logging.ERROR, noiselevel=-1)
			continue
		except CacheError as e:
			writemsg_level("!!! Unable to access cache entry: %s %s\n" % \
				(cpv, e), level=logging.ERROR, noiselevel=-1)
			continue

		if eb_mtime is None:
			writemsg_level("!!! Missing ebuild mtime: %s\n" % (cpv,),
				level=logging.ERROR, noiselevel=-1)
			continue

		try:
			eb_mtime = long(eb_mtime)
		except ValueError:
			writemsg_level("!!! Invalid ebuild mtime: %s %s\n" % \
				(cpv, eb_mtime), level=logging.ERROR, noiselevel=-1)
			continue

		if ec_mtimes is None:
			writemsg_level("!!! Missing eclass mtimes: %s\n" % (cpv,),
				level=logging.ERROR, noiselevel=-1)
			continue

		if modified_eclasses.intersection(ec_mtimes):
			continue

		missing_eclasses = set(ec_mtimes).difference(ec_names)
		if missing_eclasses:
			writemsg_level("!!! Non-existent eclass(es): %s %s\n" % \
				(cpv, sorted(missing_eclasses)), level=logging.ERROR,
				noiselevel=-1)
			continue

		eb_path = os.path.join(portdir, relative_eb_path)
		try:
			current_eb_mtime = os.stat(eb_path)
		except OSError:
			writemsg_level("!!! Missing ebuild: %s\n" % \
				(cpv,), level=logging.ERROR, noiselevel=-1)
			continue

		inconsistent = False
		for ec, (ec_path, ec_mtime) in ec_mtimes.items():
			updated_mtime = updated_ec_mtimes.get(ec)
			if updated_mtime is not None and updated_mtime != ec_mtime:
				writemsg_level("!!! Inconsistent eclass mtime: %s %s\n" % \
					(cpv, ec), level=logging.ERROR, noiselevel=-1)
				inconsistent = True
				break

		if inconsistent:
			continue

		if current_eb_mtime != eb_mtime:
			os.utime(eb_path, (eb_mtime, eb_mtime))

		for ec, (ec_path, ec_mtime) in ec_mtimes.items():
			if ec in updated_ec_mtimes:
				continue
			ec_path = os.path.join(ec_dir, ec + ".eclass")
			current_mtime = os.stat(ec_path)[stat.ST_MTIME]
			if current_mtime != ec_mtime:
				os.utime(ec_path, (ec_mtime, ec_mtime))
			updated_ec_mtimes[ec] = ec_mtime

	return os.EX_OK

def load_emerge_config(trees=None):
	kwargs = {}
	for k, envvar in (("config_root", "PORTAGE_CONFIGROOT"), ("target_root", "ROOT")):
		v = os.environ.get(envvar, None)
		if v and v.strip():
			kwargs[k] = v
	trees = portage.create_trees(trees=trees, **kwargs)

	for root, root_trees in trees.items():
		settings = root_trees["vartree"].settings
		settings._init_dirs()
		setconfig = load_default_config(settings, root_trees)
		root_trees["root_config"] = RootConfig(settings, root_trees, setconfig)

	settings = trees[trees._target_eroot]['vartree'].settings
	mtimedbfile = os.path.join(settings['EROOT'], portage.CACHE_PATH, "mtimedb")
	mtimedb = portage.MtimeDB(mtimedbfile)
	portage.output._init(config_root=settings['PORTAGE_CONFIGROOT'])
	QueryCommand._db = trees
	return settings, trees, mtimedb

def chk_updated_cfg_files(eroot, config_protect):
	target_root = eroot
	result = list(
		portage.util.find_updated_config_files(target_root, config_protect))

	for x in result:
		writemsg_level("\n %s " % (colorize("WARN", "* IMPORTANT:"),),
			level=logging.INFO, noiselevel=-1)
		if not x[1]: # it's a protected file
			writemsg_level("config file '%s' needs updating.\n" % x[0],
				level=logging.INFO, noiselevel=-1)
		else: # it's a protected dir
			if len(x[1]) == 1:
				head, tail = os.path.split(x[1][0])
				tail = tail[len("._cfg0000_"):]
				fpath = os.path.join(head, tail)
				writemsg_level("config file '%s' needs updating.\n" % fpath,
					level=logging.INFO, noiselevel=-1)
			else:
				writemsg_level("%d config files in '%s' need updating.\n" % \
					(len(x[1]), x[0]), level=logging.INFO, noiselevel=-1)

	if result:
		print(" "+yellow("*")+" See the "+colorize("INFORM","CONFIGURATION FILES")\
				+ " section of the " + bold("emerge"))
		print(" "+yellow("*")+" man page to learn how to update config files.")

def display_news_notification(root_config, myopts):
	if "news" not in root_config.settings.features:
		return
	portdb = root_config.trees["porttree"].dbapi
	vardb = root_config.trees["vartree"].dbapi
	news_counts = count_unread_news(portdb, vardb)
	display_news_notifications(news_counts)

def getgccversion(chost):
	"""
	rtype: C{str}
	return:  the current in-use gcc version
	"""

	gcc_ver_command = 'gcc -dumpversion'
	gcc_ver_prefix = 'gcc-'

	gcc_not_found_error = red(
	"!!! No gcc found. You probably need to 'source /etc/profile'\n" +
	"!!! to update the environment of this terminal and possibly\n" +
	"!!! other terminals also.\n"
	)

	mystatus, myoutput = subprocess_getstatusoutput("gcc-config -c")
	if mystatus == os.EX_OK and myoutput.startswith(chost + "-"):
		return myoutput.replace(chost + "-", gcc_ver_prefix, 1)

	mystatus, myoutput = subprocess_getstatusoutput(
		chost + "-" + gcc_ver_command)
	if mystatus == os.EX_OK:
		return gcc_ver_prefix + myoutput

	mystatus, myoutput = subprocess_getstatusoutput(gcc_ver_command)
	if mystatus == os.EX_OK:
		return gcc_ver_prefix + myoutput

	portage.writemsg(gcc_not_found_error, noiselevel=-1)
	return "[unavailable]"
